Safety locking means for laundry machines



Oct. 27, 1959 G. n. CONLEE SAFETY LOCKING MEANS FOR LAUNDRY MACHINES Filed Jan. 25, 1956 4 Sheets-Sheet 1 Ira/641261 soy-9e D corzea 40 $6 SPIN Oct. 27, 1959 a. D. CONLEE y 2,910,317

SAFETY LOCKING MEANS FOR LAUNDRY MACHINES Filed Jan. 25, 1956 4 Sheets-Sheet 2 SLO LOCK

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SAFETY LOCKING MEANS FOR LAUNDRY MACHINES Filed Jan. 25, 1956 V 4 Sheets-Sheet 3 George/D Corzflae/ dd. 2% /W W I G. D. CONLEE SAFETY LOCKING MEANS FOR LAUNDRY MACHINES Filed Jan. 25, 1956 Oct. 27 1959 4 Sheets-Sheet 4 r; all co roaa United States Patent SAFETY LOCKING MEANS FOR LAUNDRY MACHINES George D. Coulee, Ripon, Wis, assignor, by mesne assignments, to McGraw-Edison Company, a corporation of Delaware Application January 25, 1956, Serial No. 561,288

4 Claims. (Cl. 292-64) The invention relates to laundry machines of the type in which a washing operation is effected by agitating liquid and material to be washed in a tub or receptacle which is subsequently rotated at high speed to extract excess liquid from the material, and it is more particularly concerned with improved safety locking means for the access doors of such machines.

One object of the invention is to provide in a machine of the above general character in which the washing, rinsing and extracting operations are effected in an automatically controlled cycle, novel means for positively locking the access door during selected portions of the operating cycle and unlocking the door in other portions of the cycle. a

A more specific object is to provide means for locking the access door of the machine in closed position while the receptacle is rotating at high speed, including an interval required for the receptacle to come substantially to rest after the high speed drive is interrupted.

A further object is to provide locking means which permits the receptacle to be rotated at high speed with the door open for inspection or demonstration purposes while effectively locking the door during such portions of the cycle in normal washing operations.

Still another object is to provide door locking means operable under control of the timing device which controls the automatic cycling of the washing machine.

It is also an object of the invention to provide door locking mechanism for automatic washing machines which is simple in construction, dependable in operation, and which is readily applicable to a wide variety of machines.

Other objects and advantages of the invention will become apparent from the following detailed description of the preferred embodiments illustrated in the accompanying drawings, in which:

Figure l is a perspective View of a typical automatic washing machine equipped with door locking means embodying the features of the invention.

Fig. 2 is a fragmentary vertical sectional view through the top of the washing machine taken in a plane substantially on the line 2--2 of Fig. 1 and showing the access door locked in closed position.

Fig. 3 is a fragmentary sectional view taken in the same plane as Fig. 2, showing the door lock disengaged and the door in partially open position.

Fig. 4 is a fragmentary sectional view similar to Fig. 3, showing the access door closed after the locking mechanism has been operated.

Fig. 5 is a fragmentary top view of the washing machine shown in Fig. 1, partly sectioned to show details of the door locking mechanism.

Fig. 6 is a simplified circuit diagram of an automatic control system for a washing machine such as that shown in Fig. 1.

Fig. 7 is a diagram showing the timing of the different operations which make up the automatic cycle of the Washing machine.

ice

Fig. 8 is a fragmentary sectional view similar to Fig. 2, showing a modified form of door locking mechanism.

Fig. 9 is a partly sectioned plan view of the machine equipped with the locking mechanism shown in Fig. 8.

Fig. 10 is a perspective view of the support for the locking mechanism shown in Fig. 8.

Fig. 11 is a fragmentary sectional view similar to Fig. 2, showing still another form of door locking mechanism.

Fig. 12 is a partly sectioned plan view of the machine equipped with locking mechanism of the type shown in Fig. 11.

Fig. 13 is a side elevational view of the locking mechanism shown in Fig. 11.

While the invention is susceptible of various modifications and alternative constructions, certain illustrative embodiments have been shown in the drawings and will be described herein in detail. It is to be understood, however, that the detailed character of the disclosure is not intended to limit the invention to the specific forms shown nor to use with any particular type of washing machine or control system. On the contrary, the intention is to cover all modifications, alternative constructions and adaptations falling within the spirit and scope of the invention as expressed in the appended claims.

By way of illustration, the invention has been shown as incorporated in an automatic washing machine having an open top tub or receptacle 15 for clothes or other material to be washed and provided with a centrally located agitator 16 for performing the washing operation. The receptacle 15 is mounted in an upright position for rotation about a vertical axis within an outer or splash tub 17. The latter is supported by a suitable t'rame structure and enclosed in a casing 18. The particular receptacle illustrated is fitted at its open upper end with a heavy balance ring 19 shaped to provide a series of openings 20 adjacent the rim of the receptacle through which liquid is discharged when the receptacle is rotated at high speed.

Rotation of the receptacle 15 and oscillation of the agitator 16 is effected selectively by a motor M (Fig. 6) operating through a transmission (not shown) which may be of conventional construction. In automatic washing machines, such as the machine illustrated, oscillating drive for the agitator and rotating drive for the receptacle are established alternatively by an automatic control system, a typical one of which is shown diagrammatically in Fig. 6 of the drawings and described in detail hereinafter.

In the exemplary washing machine, the casing 18 is a generally rectangular box-like structure having a sup porting base 25 at its lower end and closed at its upper end by a sheet metal top panel 26. Access to the receptacle 15 for loading and unloading the material being washed is provided by an opening 27 in the top panel 26, such opening being circular or other suitable shape and preferably centered with respect to the receptacle. To prevent splashing of liquid from the receptacle and further to prevent an operator from. reaching into the machine when in operation, the access opening is fitted with a hinged door 28. To accommodate the door 28, a section 29 of the top panel 26 around the opening 27 is offset downwardly to form a recess of suflicient depth to locate the top surface of the door substantially flush with the top surface of the panel. In the particular machine illustrated, the door 28 is rectangular and the recess in the top panel 26 is complemental thereto. Preferably, the marginal edge of the offset panel section 29 is turned downwardly and outwardly as at 30 to define a smooth neck around the access opening 27.

In the exemplary washing machine the door 28 is hinged at its rear edge to the top panel. 26 to swing 3 between an open position and a closed position, the latter being shown in Fig. 2. The door, of course, may be of any preferred construction, that shown being a sheet metal panel with 'a marginal flange 31 to reinforce and stiifen it.

In accordance with one aspect of the invention, provision is made for positively locking the door 28 in closed position. Preferably this is effected by locking mechanism equipped with a power operated actuator by which the locking and unlocking actions may be coordinated with the cyclic operation of the washing machine. More specifically, the power operated locking mechanism permits positive locking of the door at times when it would be dangerous for a person to reach into the machine as, for example, when the receptacle I is spinning or rotating at high speed. In the exemplary machine, the power operated actuator for the locking mechanism comprises a solenoid Sol having a reciprocable armature 35.

While the locking mechanism may take various forms, it. preferably includes a staple-like latch element 36 (Figs. 2 and 3) mounted on the door and adapted, when the door is closed, to project through a hole 37 in the section of the .casing panel underlying the cover, in this instance, the offset edge portion 29 of the top panel 26. Cooperating with the latch element 36 is a bolt 38 supported at the side of the casing opposite the cover and adapted to be projected into and withdrawn from locking engagement with the latch element in response to energization and de-energization of the solenoid Sol.

In the preferred form of locking mechanism shown in Figs. 2-5 of the drawings, the latch element 37 comprises a metal strap 39 adapted to be welded or otherwise rigidly attached to the door 28 and having a lug 40 extending from one edge perpendicular to the plane of the door. The lug 46) is dimensioned to project through the hole 27 when the door is closed, as shown in Fig. 2, and the projecting end is formed with a transverse slot 41 (Fig. 3) dimensioned to receive the bolt 38. In the particular embodiment illustrated, the latch element is located adjacent one corner of the door 28 with the strap 39 spot welded to the flanges 31 at adjacent edges of the door.

As shown in Fig. 2, the solenoid S01 is supported within the casing 18 on a bracket 42 welded or otherwise rigidly attached to the outside of the splash tub 17 To accommodate the bolt 38, the tub is formed with an aperture in alinement with thesolenoid and this aperture is fitted with a boot 43 of rubber or other flexible material to prevent leakage of washing liquid from the tub. As shown herein, the boot is suitably apertured to receive the bolt and is shaped to allow substantial swinging movements of the bolt in a vertical plane.

The bolt 38, as shown in Figs. 2-5, comprises an elongated flat metal strip 44 having one end portion bent upwardly and then back upon itself to form a tongue 45 dimensioned to enter the slot 41 in the latch element. The other end of the strip 44 is bent over to form an arm 46 extending substantially at right angles to the strip and adapted to be hooked over a pin 47 carried by the solenoid armature 35. A tension spring 43 connected between the arm 46 and a lug 49 on the supporting bracket urges the bolt and the armature toward an unlocked position (to the left, as viewed in Fig. 3). Upon energizing of the solenoid, the armature and bolt are drawn to the right and the tongue 45 is projected through the slotddl. in the latch element. It will be observed that the tongue when projected through to slot 41 underlies the panel. section at opposite sides of the opening 37 and thus positively locks the door 23 in closed position. The spring 48, in addition to biasing the bolt 38 to open position also tends to rock the bolt in a direction to ma ntain the tongue 45 in sliding engagement with the lower face of the panel section 29 and thus alined for entering the slot in the latch element. The spring permits the bolt to swing downwardly in case the door is closed after the bolt has been operated to locking position, as shown in Fig. 4. The bolt and other parts of the machine are thus protected from damage.

The provision of the solenoid Sol for operating and releasing the door locking mechanism permits the locking and unlocking actions to be fully synchronized with particular portions of the operating cycle of an automatic washing machine. The portion of the cycle during which access to the interior of the machine presents an element of danger is, or" course, that portion in which the receptacle is spinning or rotating at high speed for centrifugal drying. It is therefore desirable to lock the door during such times, leaving it unlocked at other times for inspection or for adding water, detergents or additional material to be washed to the receptacle.

By way of illustration, a control system simplified to include only the basic elements for the automatic cycling of a washing machine and for operating the locking mechanism has been shown diagrammatically in Fig. 6 of the drawings. The timing of the various operations making up this cycle is shown diagrammatically in Fig. 7. The control system shown is electrically operated and includes a timing device in the form of a cam shaft 5!) rotatably driven at a predetermined speed by a timing motor TM. As is customary in control systems of this character, the shaft 50 is adapted to be rotated manually frornits rest position through a predetermined angle to a starting position and the motor TM rotates the shaft back to rest position to time the various operations constituting the cycle.

As shown in Fig. 6, manual rotation of the cam shaft 50 is effected by 'a control knob 51, which, in this instance, is located for convenient access on a'sl.oping control panel 52 provided adjacent the rear edge at the top of the machine casing (see'Fig. 1). The shaft is fitted with a series of cams (not shown) adapted to actuate conventional switches to start and stop the operations at the proper points .of the cycle. Operating current is supplied to the machine by way of a line or cord L-l, L-2,

equipped with a manually operable, on-and-off switch 8-1.

To simplify the description of the operation of an automatic washing machine, the cycle may conveniently be broken up into a series .ofshort intervals or time units which may be of any preferred duration and which represent the rotation of the cam shaft through a predetermined angle. A breakdown of the cycleinto forty intervals is shown diagrammatically in Fig. 7, in which the vertical-line designated 0 at the left side of the diagram represents the position of the cam shaft'when rotated to the starting position. From this-position the shaft is rotated by the motor TM back to the rest'position represented by the line at the'extreme right end of the diagram. The heavy black lines in this diagram represent closed periods of the various control switches, as

will appear presently.

Assuming that main switch 8-1 is closed, initial rotation of the cam shaft 50 to starting position results in the closure of a switch 8+2 to complete operating circuitsfor the main drive motor M and the timing motor TM. As indicated by the line in the horizontal column designated Timer, switch S2 remains closed until the cam shaft returns to rest positionQatwhich time it opens and shuts off both motors. I

With the cam shaft in starting position, switch 8-3 is closed to energize a valve actuating solenoid Sol-1 for admitting washing liquid, such as hot water, to the re- CeptacIe iS. As indicated in the column of the diagram designated Wash Water, the switch remains closed for approximately seven time units, that is, the time required to properly fill the receptacle. Shortly before the Water supply is shut olf by the opening of the switch S-3, switch S-4 is closed to energize the solenoid -so1 z which 'acts to start the agitator '16 in operation. In the exemplary machine, as indipated in the column of the diagram design'ated Agitate, switch S-4 remains closed and agitation proceeds for approximately fourteen time units.

Near the end of the agitating or washing interval, in this instance, during the last three time units, a cam on the shaft 50 closes a switch S5 to energize the valve solenoid Sol-3 to initiate the delivery of rinse water to the receptacle. As shown in the column designated Rinse Water, this valve is open for two time units and admits sufficient water to overflow the rim of the receptacle and float oft accumulated suds and scum while agitation continues.

At the end of the twentieth time unit (in this instance), switches 5-4 and 8-5 open to stop the agitator and to shut oh? the flow of water to the receptacle. Another cam on the shaft 50 then closes switch 3-6 to energize the solenoid Sol-4 which engages the high speed or spinning drive for the receptacle. As shown in the column designated Spin, the high speed rotation is of relatively short duration as, for example, four time units, which is sufiicient to discharge the wash water from the receptacle. Switch S-6 then opens to interrupt the high speed drive and allow the receptacle to come to rest.

Following the discharge of wash water, switch 8-5 is again closed to initiate delivery of rinse water to the receptacle. Flow of water continues in this instance for eight time units and during the last three of those units and for two additional time units, switch S-4 is closed to bring about operation of the agitator. This insures removal of any scum or sediment from the material being washed. When agitation stops, switch 8-6 again closes to start the final spin-dry operation. This final spinning operation continues for five time units and then stops. The timer motor and the main motor continue to run for the major portion of the last time unit of the cycle and then, as the cam shaft reaches rest position, all circuits are open to stop the motors and thus end the cycle.

In automatic control systems of the above general character, the operation of the locking mechanism is desirably placed under control of the timer, although it will be appreciated that control can be effected in a variety of other ways, if desired. In the exemplary machine, control of the locking mechanism is accomplished through the medium of a cam on the shaft 35 adapted to close a normally open switch S-7 (Fig. 6) to energize the sole- .noid Sol. As shown in the timing diagram (Fig. 7) in .the column designated Lock, switch S.7 is closed simultaneously with the closure of the spin starting switch S-6 :and consequently the locking mechanism is actuated to positively lock the door 28 as soon as the high speed drive is engaged.

As the receptacle takes appreciable time to come .to a stop after the high speed drive is disengaged, it is desirable to keep the door 28 locked for an interval until at least a major portion of the energy of the receptacle has been dissipated. To this end provision is made for maintaining the switch S-7 closed for a full time unit :after the switch S6 opens. The door is thus kept locked :and the operator prevented from trying to reach into the receptacle until it is safe to do so. Injury to the operator through carelessness or undue haste is thus precluded.

While the safety locking feature is eilective during the :normal operating cycle of the machine, nevertheless 'under controlled conditions the spinning action of the receptacle can be observed visually as when it is de- :sired to demonstrate the machine or to check the :spinning action for any reason. To do this the cam :shaft is rotated from rest position with the door 28 only partially closed, as for example, in the position shown in Fig. 3. The cam shaft may then be turned manually 'to close the switch S6 and engage the high speed drive for the receptacle. The locking solenoid Sol is energized under such conditions to shift the bolt 38 to locking position but the door, of course, will remain unlocked since d the latch element 36 is not aliued with the bolt. Con s'equently, the door may be opened fully to note the dperation of the spinning receptacle. Closure of the door with the bolt in operated position will not damage the mechanism as the bolt is merely rocked downwardly on its pivot, as shown in Fig. 4.

The locking mechanism shown in Figs. 8-10 of the drawings is similar in its mode of operation to that shown in Figs. 25. In this instance, however, a modified. form of the bolt 38a is employed, together with a modified supporting bracket 42a. The latter comprises a triangular body 55 with an upright flange 56 along one edge for attachment to the splash tub 17. A horizontally bent flange 57 at the upper edge of the bracket supports the solenoid Sol with its armature 35 facing the tub. As in the preferred form of the mechanism, the cover 28 is provided with the depending slotted latch element 36 adapted to project through the opening 37 in the top panel portion 29 of the casing.

The locking bolt 2530, as shown, comprises an elongated fiat metal strip 5% having an eye at one end for attachment to the armature 35 by the pivot pin 47.

The bolt extends from the armature through the boot in the splash tub opening as previously described. At the end remote from the solenoid, the strap 58 is bent upwardly and then back upon itself to form an outwardly facing tongue 59 engageable with the slotted latch ele ment when the solenoid is energized. I

Preferably the bracket 42 is formed at its upper edge with an extension 66 having its lateral edge portions flanged over to define spaced, parallel guides 61 and 62 in alinernent with the solenoid armature. The guides are respectively slotted as at 63 and 64 to provide clearance for the bolt 38a, the slots being dimensioned to permit limited vertical swinging of the bolt. A torsion spring 65 mounted on the pin 47 and engaging the bolt yieldably urges it upwardly to maintain the tongue 59 in sliding engagement with the lower face of the panel section 29.

The bolt 38:: is yieldably urged toward unlocked posi tion by a compression spring 66 interposed between the guide 62 and a cross pin 67 fixed to the bolt. Consequently, the door 28 remains unlocked, and can be opened at any time when the solenoid S01 is deenergized. Energization of the solenoid projects the bolt into the latch element to positively lock the door. Energization of the solenoid may be effected under control of the timer cam shaft or in any other preferred manner as heretofore described.

Another modified form of locking mechanism shown in Figs. 11-13 of the drawings, utilizes the solenoid Sol for locking and unlocking the door 28 by actuating a bolt 38b which cooperates with the latch element 36 on the door. In this form of mechanism the solenoid S01 is mounted in an upright position on a bracket 42b secured to the splash tub 17 as shown in Fig. 11. At its upper edge the bracket has an outwardly bent flange 71 defining a horizontal slideway for the bolt 38b.

The bolt 38b as shown is a fiat metal strip adapted to lie flush against the flange 71 with its inner end extending through the boot 43 into the vicinity of the latch element. Such inner end portion is offset upwardly to slide along the lower face of the panel section 29 and aline with the slot in the latch element 36. The bolt 38b is guided for movement toward and from the latch element by a pair of tangs 73 and 74 struck up from the flange 71 and respectively engaging in slots 75 and 76 in the bolt.

An integral extension at one side of the bolt is slotted to receive one arm 77 of a bell crank lever pivoted as at 78 on the bracket 42b. The other arm 79 of the bell crank lever has its tip portion 80 bent over at right angles to extend below the solenoid S01 and it is pivotally connected to the solenoid armature by the pin. 47.

A tension spring 81 connected between the lever arm 77 and the bracket 42b urges the lever in a direction to retract the bolt from the latch element and thus unlock the door 23. Energization of the solenoid Sol rocks the lever against the force exerted by the spring and projects the bolt into locking engagement with the latch element. A compression spring 82 fitted over the lever arm 77 and interposed between the upper face of the bolt and a stop washer 83 pinned to the lever holds the bolt down on its slideway. In the event that the door is closed after the bolt has been advanced to locking position, the spring yields to permit the bolt to tilt about the forward end of the flange 71 as a pivot so that no damage is done to the locking mechanism.

It will be apparent from the foregoing that the invention provides door locking mechanism of a novel and advantageous character for washing machines. The improved locking means isespecially well suited for use in so-called spindry washers of the type where the receptacle or basket is rotated at high speed to extract washing and rinsing liquids from the material being washed. In washing machines in which the operations are carried out in an automatically controlled cycle, the locking and unlocking of the door is eitected in timed relation to the machine to prevent opening of the door at times when insertion of a hand into the machine would be dangerous. In particular, the invention provides for positively locking the door of the machine to prevent access to the interior when the receptacle is being driven at high speed and for an interval after the drive is interrupted to allow the receptacle to slow down appreciably or come to a complete restv The positive action of the locking mechanism and its control by the timer which determines the cycling of the machine, insures safe operation even by inexperienced or careless users. At the same time, the improved mechanism permits visual observation of the machine at any point in the cycle under controlled conditions. More particularly, it permits the spinning action of the receptacle to be visually observed for test or demonstration purposes when the necessary steps to elfect such action are deliberately taken.

I claim:

1. Latch means for a door hinged to one face of a panel to swing between open and closed positions relative to an opening in the panel, said door being dimensioned to overlie the edge portion of the panel around 'the opening when the door is closed, said latch means comprising, in combination, a latch lug rigid with said door and extending therefrom so that one end projects through a hole in the edge portion of said panel when the door is closed, said lug having a slot in its projecting end, a solenoid supported adjacent. the other face of said panel with its armature disposed for movement to- Ward and from said lug, a bolt secured at one end to said armature for pivotal movement about a transverse axis and'longitudinal movement with the armature into and "out lot the slot in the lug to lock and unlock said door,

the opening when the door is closed, said latch means comprising, in combination, a latch'lug adjacent the'free edge of the door extending therefrom so as to project through a hole in the edge portion of the panel when the door is closed, said lug having a slot in its projecting end, an elongated latch bolt, having its end portion dirrrensioned to fit into said slot, means supporting 'said bolt for'longitudinal movement'into and out of said slot to 'lock or'unlock the door, means for imparting longitudinal movements to said bolt, said supporting means permitting said bolt to swing about an axis parallel to the plane of the door when the door is closed after the bolt has been moved to locking position, and spring means yieldably urging said bolt into a position to aline with said slot when the door is closed and said bolt is in unlocked position.

3. Latch means for a door hinged to one face of a panel to swing between open and closed positions relative to an opening in the panel, said door being dimensioned to overlie the edge portion of the panel around the opening when the door is closed, said latch means comprising, in combination, a latch lug adjacent the free edge of the door extending therefrom so as to project through a hole in the edge portion of thepanel when the door is closed, said lug having a slot in its projecting end, an elongated latch bolt having its end portion dimensioned to fit into said slot, means supporting said bolt for longitudinal movement into and out of said slot, spring means yieldably urging the bolt away from said slot to an unlocked position, means for shiftingsaid bolt against the action of said spring means'to project it into said slot and thereby lock the door, said supporting means permitting said bolt to move transversely of its normal path of movement away from said door when the door is closed after the bolt has been moved to locking position, said spring means resisting said transverse-movement and acting to restore thebolt to normal position in alinement with said slot upon return of the bolt to unlocked position.

4. Latchmeans for a door hinged to'one face of a panel to swing between open and closed positions relative to an opening in the panel, said doorbeing dimensioned to overlie the edge portion of the panel around the opening when the door is clo'sed,-said latch means comprising, in combination, a latch lug adjacent the free edge of the door extending therefrom soas to project through a hole in the edge portion 'of thepanel when the door is closed, said lug having a slot in its projecting end, 'an elongated latch bolt having its endportion dimensioned to fit into said slot, means including a flexible boot supporting said bolt for longitudinal movement into and out of said slot, means for shiftingsaid bolt longitudinally between door locking and unlocking positions, said boot yielding to permit said bolt to swing away from the door when the latter is closed with the bolt in position, and spring means yieldably urging said bolt into position to aline with said slot when the door is closed with the bolt in unlocked position.

References Cited in the file of this patent UNITED STATES PATENTS 2,176,954 Clark Oct. 24, 1939 2,637,578 Gaona May 15, 1953 2,716,567 Turcott Aug. 30, 1955 2,738,072 Knight 'Mar. 13, 1956 

